Ferroelectric smectic liquid crystal device having a bistable alignment state providing two stable orientation states

A ferroelectric smectic liquid crystal device, comprising:

• (a) a pair of substrates each provided with a uniaxial alignment axis, the alignment axes on the pair of substrates being substantially parallel with each other and having an identical axis direction;
• (b) a ferroelectric smectic liquid crystal disposed between the pair of substrates in a bistable alignment state providing two stable orientation states having an inclination of forming a connected pair of a hair pin defect and a lightning defect and further in such a first alignment state that the hair pin defect is formed after the lightning defect in the uniaxial alignment axis direction;
• and
• (c) means for optically discriminating the two stable orientation states.

A ferroelectric smectic liquid crystal device, comprising:

• (a) a pair of substrates each provided with a uniaxial alignment axis;
• (b) a ferroelectric smectic liquid crystal disposed between the pair of substrates in a bistable alignment state providing two stable orientation states, said ferroelectric smectic liquid crystal yielding smectic C phase on a higher temperature side than its ferroelectric smectic phase and the liquid crystal molecules being aligned to form a pre-tilt angle of 2 degrees or larger with respect to a substrate face in the temperature range of the smectic C phase, said ferroelectric smectic liquid crystal having been formed through the smectic A phase on temperature decrease;
• and
• (c) means for optically discriminating the two stable orientation states.